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From: Luca BRUNO <>
Subject: Re: [musl] musl resolver handling of "search ." in /etc/resolv.conf
Date: Fri, 2 Sep 2022 08:09:00 +0000	[thread overview]
Message-ID: <20220902080900.0291d2c8@ephyra> (raw)
In-Reply-To: <>

On Thu, 1 Sep 2022 14:01:53 -0400
Rich Felker <> wrote:

> > From my observations, option 1 is consistent with other libc's
> > behavior. But it has the above caveat that it needs additional
> > caching to avoid duplicate root-queries on negative responses.
> > If it isn't too invasive to implement, that would be my preferred
> > one.  
> I'm not clear what additional caching you have in mind. AFAICT the
> search loop can just set a flag if it searched root already, and the
> final root query can be skipped if it's reached and the flag is set.

Yes sorry, poor choice of wording from my side, that was the additional
logic I was hinting to.

For future reference, this bug was observed in the wild due to a
combination of recent systemd (>= v247) and kubernetes (= 1.25.0).
The on-host systemd behavior is on purpose, while the logic on
kubernetes side was not completely expected.
A bugfix for kubernetes is being assembled right now to avoid triggering
this case, see
But the same situation may crop up with other non-kubernetes runtimes,
if they try to blindly forward/merge the "search ." from the host

Ciao, Luca

  reply	other threads:[~2022-09-02  8:09 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-08-31 17:33 Dalton Hubble
2022-08-31 23:59 ` Rich Felker
2022-09-01  1:32   ` Jeffrey Walton
2022-09-01 12:45     ` Rich Felker
2022-09-01 16:03       ` Luca BRUNO
2022-09-01 18:01         ` Rich Felker
2022-09-02  8:09           ` Luca BRUNO [this message]
2022-09-19 17:18           ` Rich Felker

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